Search
Use the search bar or filters below to find any TAPPI product or publication.
Filters
Content Type
Publications
Level of Knowledge
Committees
Event Type
Collections
Journal articles
Permeability simulation for filled paper based on three-dimensional structural model developed by X-ray computed tomography scanning, TAPPI Journal March 2026
ABSTRACT: In this study, an in-depth exploration of filled paper was conducted to understand its structural and permeability characteristics. Cotton linter pulp and precipitated calcium carbonate (PCC) filler were utilized to prepare pure fiber paper, and PCC1 and PCC2 filled papers with different filler particle sizes. Then, the pore structure parameters of paper samples were characterized by mercury intrusion porosimetry, and the X-ray computed tomography (X-CT) scanning was carried out. Subsequently, the 3D microstructures were established based on the X-CT slice images, and the filler characteristic parameters and filler 3D distribution were quantitatively analyzed. Finally, permeation simulations in the thickness and horizontal directions were performed. The findings indicate that filling changes the paper porosity, and the pore tortuosity varies with direction. The estimated pore•throat radius distribution shows specific patterns for different papers. The fillers have different distribution characteristics in the paper samples. Moreover, the paper permeability differs with direction, with smallsized filler having a significant impact on fluid penetration in the thickness direction. Overall, this study provides an effective method for investigating internal paper filler and its distribution, which contributes to the understanding of paper structure•performance relationships.
Journal articles
Moisture performance of silica-paper hybrids in the hygroscopic range, TAPPI Journal March 2026
ABSTRACT: Vapor retarders, crucial in building constructions, are traditionally made from plastic-based materials, raising environmental concerns due to the use of fossil materials. This study explores the potential of functionalized papers, particularly silica-paper hybrids, as sustainable alternatives. This work delves into the moisture properties of sol-gel coated linter papers, considering the water vapor permeability and physisorption behavior following DIN EN ISO 12572 and DIN EN ISO 12571. The study addresses hysteresis, noting the lower hysteresis of mesoporous coatings in comparison to dense coatings and implying benefits in moisture release. Findings underscore the need for a nuanced understanding of coating characteristics and their impact on sorption. In order to better assess the relationship between the coating content of the papers and their specific sorption properties, further investigations, such as the measurement of specific surface properties (e.g., specific surface area), are required. The findings of the water vapor diffusion resistance measurement study demonstrate a correlation between the observed resistance and the vapor levels. The results show that the water vapor diffusion resistance is elevated at lower vapor levels when compared to higher levels. This particular material behavior is typically employed within the construction industry for the utilization of moisture-variable water vapor retarders. The silica-paper hybrids exhibit a response that indicates the potential for advancement into a moisture-variable water vapor barrier.
Journal articles
Effects of in-plane straining on the out-of-plane delamination properties of paperboard, TAPPI Journal March 2026
ABSTRACT: Delamination strength is an essential property for the creasing and folding operations of paperboard into boxes. Due to fixation during creasing, the paperboard suffers in-plane straining. In the present study, we aim to increase our understanding of how in-plane straining affects the delamination properties of paperboard. Samples of paperboard were first strained in in-plane tensile loading, both in the machine-direction and in the cross-direction. Afterward, the paperboard is loaded in the out-of-plane (ZD) direction. Three different grades of commercial paperboard from two major manufacturers were tested in a climate-controlled lab. The results showed similar results for all grades of paperboard, with the delamination strength and the out-of-plane stiffness decreasing virtually linearly with pre-straining. With about 5% plastic in-plane straining, the strength was reduced by about 20% and the stiffness decreased by more than 50% for all grades of paperboard. Normalizing the strength and the stiffness with their values without pre-straining reveals virtually the same relation for all grades of paperboard. If proven to be a general result, this will prove valuable in reducing the demand for experiments.